The long-term objective of the proposed research is to develop a rapid method for the diagnosis of tuberculosis. A piezoelectric biosensor employing antibodies to soluble mycobacterial antigens will be used to detect these specific antigens and/or whole mycobacteria. Detection of mycobacterial antigens in a liquid phase will allow the diagnosis of mycobacterial infection in biological fluids such as sputum, bronchoalveolar lavage fluid, cerebral spinal fluid and synovial fluid. Ultimately, gas or vapor phase detection of mycobacterial antigens by a piezo-immunosensor would allow rapid diagnosis of pulmonary tuberculosis by detection of mycobacterial antigens in expired human breath. The feasibility of this novel approach to the diagnosis of tuberculosis will be tested using monoclonal and polyclonal antibodies to specific mycobacterial antigens. The antibodies will be coupled to gold electrodes on AT-cut 9 MHzquartz crystals. The resulting piezoelectric- immunosensor will be tested for its ability to detect mycobacterial antigens in culture supernatants and in solutions of antigen vaporized by a nebulizer.